Acute remodeling of an adjoining aneurysm after endovascular treatment of a ruptured splanchnic arterial aneurysm: a case of clinically diagnosed segmental arterial mediolysis.

A 61-year-old woman with multiple splanchnic arterial aneurysms (SAAs) was transferred to our hospital in a state of shock. She underwent coil embolization under the diagnosis of ruptured pancreaticoduodenal artery aneurysm. Follow-up computed tomography performed 2 weeks later showed rapid enlargement of a gastric artery aneurysm, and she underwent an additional embolization. Atherosclerotic, inflammatory or hereditary causes were excluded, and the patient was clinically diagnosed with segmental arterial mediolysis accompanied by multiple SAAs, one of which showed acute remodeling after endovascular treatment.